With nearly $1 billion down the drain, and precious years of education wasted for hundreds of children, Mayor Bill de Blasio is finally giving up on his Renewal Schools program. Except he’s not really even doing that.

The city had to close 23 of the original 90-plus schools; 21 more have “graduated out,” thanks to modest improvements. But the remaining 50 will get the same “medicine” (extra funding and social services support) exactly as before.

The only real change is to drop the Renewal brand — because it accurately warns parents that their kids would be better off at another school. That leads to transfers — and can bring a school’s enrollment down so far that it has to close. Indeed, it explains most of those 23 Renewal closures.

Yet the true purpose of Renewal was exclusively to avoid closing schools, even terrible ones, because the teachers union hates it when members have to find new placements. It bitterly resented the Bloom­berg-era approach of closing down bad schools and opening new ones in their place, and de Blasio was happy to oblige.

Never mind that he thereby condemned students to (at best) sub-par education while the city made a show of trying to turn the schools around.

Now de Blasio’s new chancellor, Richard Carranza, is explaining that there’s no silver bullet to turn around schools. But that doesn’t excuse Renewal’s failure; it explains why it was a con from the start.

Then Carranza falls back on blaming “privilege” — when enrollment in New York’s public schools is 80 percent minority.

Yes, higher-income people find ways for their kids to attend good schools. But it’s Carranza’s job, and de Blasio’s, to offer the same opportunity to lower-income folks.

The city’s best charter schools keep showing how to do exactly that — which is why the mayor and the chancellor resent them.

Carranza recently warned charter networks to stop advertising the fact that they offer a better chance at a good education. Now de Blasio is killing the “Renewal” label because it’s a warning that the school stinks.

In short, they’re far more dedicated to keeping parents ignorant than to educating children.